#pragma once

//#include <srs_http_stack.hpp>
#include <srs_core.hpp>

#if !defined(SRS_EXPORT_LIBRTMP)

#include <map>
#include <string>
#include <vector>

#ifndef _WIN32
#include <sys/uio.h>
#endif

class SrsFileReader;
class SrsHttpHeader;
class ISrsHttpMessage;
class SrsHttpMuxEntry;
class ISrsHttpResponseWriter;

// http specification
// CR             = <US-ASCII CR, carriage return (13)>
#define SRS_HTTP_CR SRS_CONSTS_CR // 0x0D
// LF             = <US-ASCII LF, linefeed (10)>
#define SRS_HTTP_LF SRS_CONSTS_LF // 0x0A
// SP             = <US-ASCII SP, space (32)>
#define SRS_HTTP_SP ' ' // 0x20
// HT             = <US-ASCII HT, horizontal-tab (9)>
#define SRS_HTTP_HT '\x09' // 0x09

// HTTP/1.1 defines the sequence CR LF as the end-of-line marker for all
// protocol elements except the entity-body (see appendix 19.3 for
// tolerant applications).
#define SRS_HTTP_CRLF "\r\n" // 0x0D0A
#define SRS_HTTP_CRLFCRLF "\r\n\r\n" // 0x0D0A0D0A

// @see ISrsHttpMessage._http_ts_send_buffer
#define SRS_HTTP_TS_SEND_BUFFER_SIZE 4096

// for ead all of http body, read each time.
#define SRS_HTTP_READ_CACHE_BYTES 4096

// default http listen port.
#define SRS_DEFAULT_HTTP_PORT 80

// for http parser macros
#define SRS_CONSTS_HTTP_OPTIONS HTTP_OPTIONS
#define SRS_CONSTS_HTTP_GET HTTP_GET
#define SRS_CONSTS_HTTP_POST HTTP_POST
#define SRS_CONSTS_HTTP_PUT HTTP_PUT
#define SRS_CONSTS_HTTP_DELETE HTTP_DELETE

// Error replies to the request with the specified error message and HTTP code.
// The error message should be plain text.
extern int srs_go_http_error(ISrsHttpResponseWriter* w, int code);
extern int srs_go_http_error(ISrsHttpResponseWriter* w, int code, const std::string& error);

// get the status text of code.
extern std::string srs_generate_http_status_text(int status);

// bodyAllowedForStatus reports whether a given response status code
// permits a body.  See RFC2616, section 4.4.
extern bool srs_go_http_body_allowd(int status);

// DetectContentType implements the algorithm described
// at http://mimesniff.spec.whatwg.org/ to determine the
// Content-Type of the given data.  It considers at most the
// first 512 bytes of data.  DetectContentType always returns
// a valid MIME type: if it cannot determine a more specific one, it
// returns "application/octet-stream".
extern std::string srs_go_http_detect(char* data, int size);

// state of message
enum SrsHttpParseState {
    SrsHttpParseStateInit = 0,
    SrsHttpParseStateStart,
    SrsHttpParseStateHeaderComplete,
    SrsHttpParseStateMessageComplete
};

// A Header represents the key-value pairs in an HTTP header.
class SrsHttpHeader {
private:
    std::map<std::string, std::string> headers;
public:
    SrsHttpHeader();
    virtual ~SrsHttpHeader();
public:
    // Add adds the key, value pair to the header.
    // It appends to any existing values associated with key.
    virtual void set(const std::string& key, const std::string& value);
    // Get gets the first value associated with the given key.
    // If there are no values associated with the key, Get returns "".
    // To access multiple values of a key, access the map directly
    // with CanonicalHeaderKey.
    virtual std::string get(const std::string& key);
public:
    /**
     * get the content length. -1 if not set.
     */
    virtual int64_t content_length();
    /**
     * set the content length by header "Content-Length"
     */
    virtual void set_content_length(int64_t size);
public:
    /**
     * get the content type. empty string if not set.
     */
    virtual std::string content_type();
    /**
     * set the content type by header "Content-Type"
     */
    virtual void set_content_type(const std::string& ct);
public:
    /**
     * write all headers to string stream.
     */
    virtual void write(std::stringstream& ss);
};

// A ResponseWriter interface is used by an HTTP handler to
// construct an HTTP response.
// Usage 1, response with specified length content:
//      ISrsHttpResponseWriter* w; // create or get response.
//      std::string msg = "Hello, HTTP!";
//      w->header()->set_content_type("text/plain; charset=utf-8");
//      w->header()->set_content_length(msg.length());
//      w->write_header(SRS_CONSTS_HTTP_OK);
//      w->write((char*)msg.data(), (int)msg.length());
//      w->final_request(); // optional flush.
// Usage 2, response with HTTP code only, zero content length.
//      ISrsHttpResponseWriter* w; // create or get response.
//      w->header()->set_content_length(0);
//      w->write_header(SRS_CONSTS_HTTP_OK);
//      w->final_request();
// Usage 3, response in chunked encoding.
//      ISrsHttpResponseWriter* w; // create or get response.
//      std::string msg = "Hello, HTTP!";
//      w->header()->set_content_type("application/octet-stream");
//      w->write_header(SRS_CONSTS_HTTP_OK);
//      w->write((char*)msg.data(), (int)msg.length());
//      w->write((char*)msg.data(), (int)msg.length());
//      w->write((char*)msg.data(), (int)msg.length());
//      w->write((char*)msg.data(), (int)msg.length());
//      w->final_request(); // required to end the chunked and flush.
class ISrsHttpResponseWriter {
public:
    ISrsHttpResponseWriter();
    virtual ~ISrsHttpResponseWriter();
public:
    // when chunked mode,
    // final the request to complete the chunked encoding.
    // for no-chunked mode,
    // final to send request, for example, content-length is 0.
    virtual int final_request() = 0;

    // Header returns the header map that will be sent by WriteHeader.
    // Changing the header after a call to WriteHeader (or Write) has
    // no effect.
    virtual SrsHttpHeader* header() = 0;

    // Write writes the data to the connection as part of an HTTP reply.
    // If WriteHeader has not yet been called, Write calls WriteHeader(http.StatusOK)
    // before writing the data.  If the Header does not contain a
    // Content-Type line, Write adds a Content-Type set to the result of passing
    // the initial 512 bytes of written data to DetectContentType.
    // @param data, the data to send. NULL to flush header only.
    virtual int write(char* data, int size) = 0;
    /**
     * for the HTTP FLV, to writev to improve performance.
     */
    virtual int writev(iovec* iov, int iovcnt, ssize_t* pnwrite) = 0;

    // WriteHeader sends an HTTP response header with status code.
    // If WriteHeader is not called explicitly, the first call to Write
    // will trigger an implicit WriteHeader(http.StatusOK).
    // Thus explicit calls to WriteHeader are mainly used to
    // send error codes.
    // @remark, user must set header then write or write_header.
    virtual void write_header(int code) = 0;
};

/**
 * the reader interface for http response.
 */
class ISrsHttpResponseReader {
public:
    ISrsHttpResponseReader();
    virtual ~ISrsHttpResponseReader();
public:
    /**
     * whether response read EOF.
     */
    virtual bool eof() = 0;
    /**
     * read from the response body.
     * @param data, the buffer to read data buffer to.
     * @param nb_data, the max size of data buffer.
     * @param nb_read, the actual read size of bytes. NULL to ignore.
     * @remark when eof(), return error.
     * @remark for some server, the content-length not specified and not chunked,
     *      which is actually the infinite chunked encoding, which after http header
     *      is http response data, it's ok for browser. that is,
     *      when user call this read, please ensure there is data to read(by content-length
     *      or by chunked), because the sdk never know whether there is no data or
     *      infinite chunked.
     */
    virtual int read(char* data, int nb_data, int* nb_read) = 0;
};

// Objects implementing the Handler interface can be
// registered to serve a particular path or subtree
// in the HTTP server.
//
// ServeHTTP should write reply headers and data to the ResponseWriter
// and then return.  Returning signals that the request is finished
// and that the HTTP server can move on to the next request on
// the connection.
class ISrsHttpHandler {
public:
    SrsHttpMuxEntry* entry;
public:
    ISrsHttpHandler();
    virtual ~ISrsHttpHandler();
public:
    virtual bool is_not_found();
    virtual int serve_http(ISrsHttpResponseWriter* w, ISrsHttpMessage* r) = 0;
};

// Redirect to a fixed URL
class SrsHttpRedirectHandler : public ISrsHttpHandler {
private:
    std::string url;
    int code;
public:
    SrsHttpRedirectHandler(const std::string& u, int c);
    virtual ~SrsHttpRedirectHandler();
public:
    virtual int serve_http(ISrsHttpResponseWriter* w, ISrsHttpMessage* r);
};

// NotFound replies to the request with an HTTP 404 not found error.
class SrsHttpNotFoundHandler : public ISrsHttpHandler {
public:
    SrsHttpNotFoundHandler();
    virtual ~SrsHttpNotFoundHandler();
public:
    virtual bool is_not_found();
    virtual int serve_http(ISrsHttpResponseWriter* w, ISrsHttpMessage* r);
};

// FileServer returns a handler that serves HTTP requests
// with the contents of the file system rooted at root.
//
// To use the operating system's file system implementation,
// use http.Dir:
//
//     http.Handle("/", SrsHttpFileServer("/tmp"))
//     http.Handle("/", SrsHttpFileServer("static-dir"))
class SrsHttpFileServer : public ISrsHttpHandler {
protected:
    std::string dir;
public:
    SrsHttpFileServer(const std::string& root_dir);
    virtual ~SrsHttpFileServer();
public:
    virtual int serve_http(ISrsHttpResponseWriter* w, ISrsHttpMessage* r);
private:
    /**
     * serve the file by specified path
     */
    virtual int serve_file(ISrsHttpResponseWriter* w, ISrsHttpMessage* r, const std::string& fullpath);
    virtual int serve_flv_file(ISrsHttpResponseWriter* w, ISrsHttpMessage* r, const std::string& fullpath);
    virtual int serve_mp4_file(ISrsHttpResponseWriter* w, ISrsHttpMessage* r, const std::string& fullpath);
protected:
    /**
     * when access flv file with x.flv?start=xxx
     */
    virtual int serve_flv_stream(ISrsHttpResponseWriter* w, ISrsHttpMessage* r, const std::string& fullpath, int offset);
    /**
     * when access mp4 file with x.mp4?range=start-end
     * @param start the start offset in bytes.
     * @param end the end offset in bytes. -1 to end of file.
     * @remark response data in [start, end].
     */
    virtual int serve_mp4_stream(ISrsHttpResponseWriter* w, ISrsHttpMessage* r, const std::string& fullpath, int start, int end);
protected:
    /**
     * copy the fs to response writer in size bytes.
     */
    virtual int copy(ISrsHttpResponseWriter* w, SrsFileReader* fs, ISrsHttpMessage* r, int size);
};

// the mux entry for server mux.
// the matcher info, for example, the pattern and handler.
class SrsHttpMuxEntry {
public:
    bool explicit_match;
    ISrsHttpHandler* handler;
    std::string pattern;
    bool enabled;
public:
    SrsHttpMuxEntry();
    virtual ~SrsHttpMuxEntry();
};

/**
 * the hijacker for http pattern match.
 */
class ISrsHttpMatchHijacker {
public:
    ISrsHttpMatchHijacker();
    virtual ~ISrsHttpMatchHijacker();
public:
    /**
     * when match the request failed, no handler to process request.
     * @param request the http request message to match the handler.
     * @param ph the already matched handler, hijack can rewrite it.
     */
    virtual int hijack(ISrsHttpMessage* request, ISrsHttpHandler** ph) = 0;
};

/**
 * the server mux, all http server should implements it.
 */
class ISrsHttpServeMux {
public:
    ISrsHttpServeMux();
    virtual ~ISrsHttpServeMux();
public:
    virtual int serve_http(ISrsHttpResponseWriter* w, ISrsHttpMessage* r) = 0;
};

// ServeMux is an HTTP request multiplexer.
// It matches the URL of each incoming request against a list of registered
// patterns and calls the handler for the pattern that
// most closely matches the URL.
//
// Patterns name fixed, rooted paths, like "/favicon.ico",
// or rooted subtrees, like "/images/" (note the trailing slash).
// Longer patterns take precedence over shorter ones, so that
// if there are handlers registered for both "/images/"
// and "/images/thumbnails/", the latter handler will be
// called for paths beginning "/images/thumbnails/" and the
// former will receive requests for any other paths in the
// "/images/" subtree.
//
// Note that since a pattern ending in a slash names a rooted subtree,
// the pattern "/" matches all paths not matched by other registered
// patterns, not just the URL with Path == "/".
//
// Patterns may optionally begin with a host name, restricting matches to
// URLs on that host only.  Host-specific patterns take precedence over
// general patterns, so that a handler might register for the two patterns
// "/codesearch" and "codesearch.google.com/" without also taking over
// requests for "http://www.google.com/".
//
// ServeMux also takes care of sanitizing the URL request path,
// redirecting any request containing . or .. elements to an
// equivalent .- and ..-free URL.
class SrsHttpServeMux : public ISrsHttpServeMux {
private:
    // the pattern handler, to handle the http request.
    std::map<std::string, SrsHttpMuxEntry*> entries;
    // the vhost handler.
    // when find the handler to process the request,
    // append the matched vhost when pattern not starts with /,
    // for example, for pattern /live/livestream.flv of vhost ossrs.net,
    // the path will rewrite to ossrs.net/live/livestream.flv
    std::map<std::string, ISrsHttpHandler*> vhosts;
    // all hijackers for http match.
    // for example, the hstrs(http stream trigger rtmp source)
    // can hijack and install handler when request incoming and no handler.
    std::vector<ISrsHttpMatchHijacker*> hijackers;
public:
    SrsHttpServeMux();
    virtual ~SrsHttpServeMux();
public:
    /**
     * initialize the http serve mux.
     */
    virtual int initialize();
    /**
     * hijack the http match.
     */
    virtual void hijack(ISrsHttpMatchHijacker* h);
    virtual void unhijack(ISrsHttpMatchHijacker* h);
public:
    // Handle registers the handler for the given pattern.
    // If a handler already exists for pattern, Handle panics.
    virtual int handle(const std::string& pattern, ISrsHttpHandler* handler);
    // whether the http muxer can serve the specified message,
    // if not, user can try next muxer.
    virtual bool can_serve(ISrsHttpMessage* r);
    // interface ISrsHttpServeMux
public:
    virtual int serve_http(ISrsHttpResponseWriter* w, ISrsHttpMessage* r);
private:
    virtual int find_handler(ISrsHttpMessage* r, ISrsHttpHandler** ph);
    virtual int match(ISrsHttpMessage* r, ISrsHttpHandler** ph);
    virtual bool path_match(const std::string& pattern, const std::string& path);
};

// for http header.
typedef std::pair<std::string, std::string> SrsHttpHeaderField;

// A Request represents an HTTP request received by a server
// or to be sent by a client.
//
// The field semantics differ slightly between client and server
// usage. In addition to the notes on the fields below, see the
// documentation for Request.Write and RoundTripper.
//
// There are some modes to determine the length of body:
//      1. content-length and chunked.
//      2. user confirmed infinite chunked.
//      3. no body or user not confirmed infinite chunked.
// For example:
//      ISrsHttpMessage* r = ...;
//      while (!r->eof()) r->read(); // read in mode 1 or 3.
// For some server, we can confirm the body is infinite chunked:
//      ISrsHttpMessage* r = ...;
//      r->enter_infinite_chunked();
//      while (!r->eof()) r->read(); // read in mode 2
// @rmark for mode 2, the infinite chunked, all left data is body.
class ISrsHttpMessage {
private:
    /**
     * use a buffer to read and send ts file.
     */
    // TODO: FIXME: remove it.
    char* _http_ts_send_buffer;
public:
    ISrsHttpMessage();
    virtual ~ISrsHttpMessage();
public:
    /**
     * the http request level cache.
     */
    virtual char* http_ts_send_buffer();
public:
    virtual u_int8_t method() = 0;
    virtual u_int16_t status_code() = 0;
    /**
     * method helpers.
     */
    virtual std::string method_str() = 0;
    virtual bool is_http_get() = 0;
    virtual bool is_http_put() = 0;
    virtual bool is_http_post() = 0;
    virtual bool is_http_delete() = 0;
    virtual bool is_http_options() = 0;
public:
    /**
     * whether should keep the connection alive.
     */
    virtual bool is_keep_alive() = 0;
    /**
     * the uri contains the host and path.
     */
    virtual const std::string uri() = 0;
    /**
     * the url maybe the path.
     */
    virtual const std::string& url() = 0;
    virtual const std::string& host() = 0;
    virtual const std::string& path() = 0;
    virtual const std::string& query() = 0;
    virtual const std::string& ext() = 0;
    /**
     * get the RESTful id,
     * for example, pattern is /api/v1/streams, path is /api/v1/streams/100,
     * then the rest id is 100.
     * @param pattern the handler pattern which will serve the request.
     * @return the REST id; -1 if not matched.
     */
    virtual int parse_rest_id(const std::string& pattern) = 0;
    virtual int parse_rest(const std::string& pattern, std::vector<std::string>& arr) = 0;
public:
    /**
     * the left all data is chunked body, the infinite chunked mode,
     * which is chunked encoding without chunked header.
     * @remark error when message is in chunked or content-length specified.
     */
    virtual int enter_infinite_chunked() = 0;
    /**
     * read body to string.
     * @remark for small http body.
     */
    virtual int body_read_all(std::string& body) = 0;
    /**
     * get the body reader, to read one by one.
     * @remark when body is very large, or chunked, use this.
     */
    virtual ISrsHttpResponseReader* body_reader() = 0;
    /**
     * the content length, -1 for chunked or not set.
     */
    virtual int64_t content_length() = 0;
public:
    /**
     * get the param in query string,
     * for instance, query is "start=100&end=200",
     * then query_get("start") is "100", and query_get("end") is "200"
     */
    virtual const std::string& query_get(const std::string& key) = 0;
    /**
     * get the headers.
     */
    virtual int request_header_count() = 0;
    virtual const std::string& request_header_key_at(int index) = 0;
    virtual const std::string& request_header_value_at(int index) = 0;
public:
    /**
     * whether the current request is JSONP,
     * which has a "callback=xxx" in QueryString.
     */
    virtual bool is_jsonp() = 0;
};

#endif
